The present invention relates to medical instrumentation apparatus. More particularly, it relates to improved housing means for an acoustic transducer.
In the art of medical diagnostics, one form of non-inevasive examination of the internal organs of a body under examination involves the use of ultrasonic transducers. These transducers are frequently mounted within a housing filled with an inert liquid and arranged to oscillate in an angularly scanning motion. The housing is generally relatively opaque to the ultrasonic pulses generated by the transducer, with the exception of a relatively transparent window or diaphragm in the operating end of the housing structure. The transducer is positioned and oscillated to direct the acoustic pulses through the diaphragm or window, into the body under examination. The acoustic pulses transmitted into that body are then reflected back toward the transducer at interfaces of tissue within the body, to produce electrical pulses which may be translated into an image of the interior of the body being examined. As noted, the housing for the transducer is filled with an inert liquid. If there are air bubbles remaining within the housing, these air bubbles will be agitated into the liquid by the oscillation of the transducer. The entrained air bubbles cause a deterioration of the transmitted and received signals, thereby interfering with an accurate imaging of the organ under examination.